WO2003014820A1 - Reflective liquid-crystal display - Google Patents
Reflective liquid-crystal display Download PDFInfo
- Publication number
- WO2003014820A1 WO2003014820A1 PCT/IB2002/002755 IB0202755W WO03014820A1 WO 2003014820 A1 WO2003014820 A1 WO 2003014820A1 IB 0202755 W IB0202755 W IB 0202755W WO 03014820 A1 WO03014820 A1 WO 03014820A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- liquid crystal
- retardation
- layer
- retardation film
- axis
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/13363—Birefringent elements, e.g. for optical compensation
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/139—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
- G02F1/1396—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent the liquid crystal being selectively controlled between a twisted state and a non-twisted state, e.g. TN-LC cell
- G02F1/1397—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent the liquid crystal being selectively controlled between a twisted state and a non-twisted state, e.g. TN-LC cell the twist being substantially higher than 90°, e.g. STN-, SBE-, OMI-LC cells
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133509—Filters, e.g. light shielding masks
- G02F1/133514—Colour filters
- G02F1/133516—Methods for their manufacture, e.g. printing, electro-deposition or photolithography
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
- G02F1/133533—Colour selective polarisers
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
- G02F1/133536—Reflective polarizers
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/13363—Birefringent elements, e.g. for optical compensation
- G02F1/133636—Birefringent elements, e.g. for optical compensation with twisted orientation, e.g. comprising helically oriented LC-molecules or a plurality of twisted birefringent sublayers
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/139—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
- G02F1/1396—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent the liquid crystal being selectively controlled between a twisted state and a non-twisted state, e.g. TN-LC cell
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/13363—Birefringent elements, e.g. for optical compensation
- G02F1/133638—Waveplates, i.e. plates with a retardation value of lambda/n
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2203/00—Function characteristic
- G02F2203/02—Function characteristic reflective
Definitions
- the present invention relates to a liquid crystal display device, comprising at least one retardation film, a nematic liquid crystal layer, and a reflective cholesteric colour filter layer.
- LCD liquid crystal displays
- This progress can be attributed to continuous improvements in size and performance and the decrease in the price of the panels.
- the design of LCDs for portable applications like cellular telephones and for demanding applications like PDAs differs strongly from the design of LCDs for high-end applications like monitors and TNs.
- low cost and low power are equally important as display image quality.
- Many challenges still remain to further improve the properties of LCDs.
- a performance issue that must be improved is, for example, the quality of the colours for reflective passive matrix displays, as initially described.
- Such display panels based on cholesteric colour filters are an attractive alternative for absorbing colour filters.
- a passive matrix display with reflective colour filters in accordance with the prior art is described in the patent document US 5 555 114.
- This document discloses a liquid crystal display including a cholesteric liquid crystal layer for selectively reflecting circularly polarised light having a specific wavelength.
- One embodiment of the inventive display basically contains a polariser, a quarter wave-plate, a liquid crystal layer, and a cholesteric colour filter layer, in sequence.
- the driven liquid crystal layer may be a layer of ferroelectric, twisted nematic or super twisted nematic liquid crystal.
- this display as described in the patent document US 5 555 114, has the problem that for twisted nematic liquid crystal, a display of high contrast that cover the entire range of the visible spectrum cannot be obtained.
- Said retardation layer preferably comprises a wide-band quarter-wave plate.
- said wide-band quarter-wave plate consists of a quarter wave plate in combination with a half wave plate, thereby enabling the use of standard, well-tested layer components.
- the front polariser, the retardation film or retardation films, the liquid crystal layer and the reflective cholesteric colour filter layer are arranged on each other in sequence.
- said device further comprises a further retardation layer which is a twisted nematic polymeric film, being arranged between the front substrate and the super twisted nematic layer, said twisted nematic polymeric layer and super twisted nematic layer have mutually opposite twist directions.
- Fig. 1 is a cross-section view of a display in accordance with the invention.
- Fig. 2 is a diagram showing the optical principle mechanism of a display in accordance with fig 1.
- Fig. 3 a is a diagram showing the optical principle mechanism in accordance with a computer simulation of a display in accordance with the invention, being optimised for obtaining high brightness.
- Fig. 3b is a diagram showing the transmission in relation to wavelength for incident light, for a display device in accordance with fig 3a.
- Fig. 4a is a diagram showing the optical principle mechanism in accordance with a computer simulation of a display in accordance with the invention, being optimised for obtaining high contrast.
- Fig. 4b is a diagram showing the transmission in relation to wavelength for incident light, for a display device in accordance with fig 4a.
- Fig. 1 is a schematic, cross-sectional view of a part of a liquid-crystal reflective display device, comprising a display cell in this case comprising a super twisted nematic liquid crystal layer 5, also referred to as a LC layer, having a twist angle within the interval 180°-270°, essentially being sandwiched between two glass substrates, a front substrate 7 and a back substrate 8.
- a polariser 1 and one or more retardation films 4 are arranged on the side of the front substrate opposing said liquid crystal layer 5.
- said combination of retardation films 4 comprises a half wave-plate 2 and a quarter wave- plate 3.
- a first electrode layer 10 and a LC orientation layer 12 are arranged in sequence. Further, between said highly twisted nematic liquid crystal layer 5 and said back substrate 8, an LC orientation layer 13 a second electrode layer 11, and a reflective cholesteric colour filter layer 6 are arranged in sequence. On the side of the back substrate opposing said reflective cholesteric colour filter layer 6 an absorption layer 9 is arranged. Said first and second electrode layers 10, 11 and the orientation layers 12, 13 are formed in accordance with prior art for super twisted nematic displays, and will not be described closer herein.
- said first and second electrode layers 10, 11 are manufactured by a transparent material, such as indium tin oxide (ITO), and are connected with a power source 14, in order to enable the generation of an electric field over the super twisted nematic liquid crystal layer 5 to create an ON and an OFF state of said display on per se known manner.
- the orientation layers are provided on both sides of the super twisted nematic liquid crystal layer in order to give the layer a desired stable orientation.
- the orientation layers 12, 13 may for example comprise a polymer, e.g. PI, being treated in accordance with prior art.
- the above-described reflective cholesteric colour filter layer 6 basically combines a reflector function, a polariser function and a colour filter function.
- the cholesteric liquid crystal phase is a chiral mesophase having a natural periodicity.
- the liquid crystals are arranged in a screwlike fashion. When the product of the birefringence of the cholesteric material and the periodicity of the liquid crystals matches the wavelength of light in the material i.e.
- the light will be reflected by means of Bragg reflection.
- the screwlike liquid crystal is either left- or right-handed.
- the cholesteric layer will reflect only light with wavelengths between p-n e and p-n 0 , where n e and n 0 are the extraordinary and the ordinary refractive indices of a uniaxially oriented phase respectively.
- said reflective cholesteric colour filter layer is based on a photosensitive cholesteric material.
- the periodicity of the cholesteric phase can be influenced by UN light.
- the cholesteric colour filter can be patternwise exposed to UN light with a grayscale mask. This process is advantageous in that only one exposure step is necessary in order to generate colours as described in patent document WO/0034808. This is a strong reduction compared to the manufacturing process of the conventional absorbing colour filter which usually involves three litographic steps for the subsequent deposition of red, green and blue filters.
- the retardation film 4 (also referred to as retardation layer) comprises two films, a half wave-plate 2, and a quarter wave-plate 3, together constituting a wide-band quarter-wave plate 4, resulting in a better overall dark state.
- a more schematic drawing, disclosing the principal optically active components of the display is disclosed in fig 2.
- FIG. 3a A first embodiment of this invention, as shown in fig 3a and 3b, will hereinafter be described.
- This configuration as schematically shown in fig 3a, comprises a right-handed 240° twisted nematic layer with an optical thickness of 0,76 ⁇ m.
- the display is of the normally black type. In this mode the off-state of the driven LC layer 5 is dark and the on-state is bright.
- this embodiment is described for the normally black mode, it is also possible to make a configuration in the normally white mode.
- the above two retardation films 2, 3 are inserted.
- a film 3 with the retardation of 140 nm in combination with a polariser makes circularly polarised light.
- a wide-band quarter-wave plate is created, resulting in a better overall dark state.
- the slow axis of the film 3, which is adjacent to the substrate, makes an angle of 30° with the vertical y-axis of the device.
- the half-wave plate 2 makes an angle of 170° with the vertical y-axis.
- the absorption axis of the polariser makes an angle of 110° with the vertical y-axis.
- the LC layer 5 switches over 315 nm ( ⁇ l/2- ⁇ ).
- a left-handed colour filter is used.
- FIG. 4a A second embodiment of this invention, as shown in fig 4a and 4b, will hereinafter be described.
- This configuration as schematically shown in fig 4a, comprises a right-handed 240° twisted nematic layer with an optical thickness of 0,76 ⁇ m.
- the display is of the normally black type. In this mode the off-state of the driven LC layer is dark and the on-state is bright.
- this embodiment is described for the normally black mode, it is also possible to make a configuration in the normally white mode.
- the above two retardation films 2, 3 are inserted.
- a film 3 with the retardation of 140 nm in combination with a polariser makes circularly polarised light.
- a wide-band quarter-wave plate is created, resulting in a better overall dark state.
- the slow axis of the film 3, which is adjacent to the substrate, makes an angle of 30° with the vertical y-axis.
- the half-wave plate 2 makes an angle of 0° with the vertical y-axis.
- the absorption axis of the polariser makes an angle of 120° with the vertical y-axis.
- the LC layer 5 switches over 315 nm ( ⁇ l/2- ⁇ ).
- a left-handed colour filter is used.
- the above described single super twisted nematic LC layer is exchanged for two super twisted nematic LC layers, having opposite twisting directions.
- the first layer, placed closer to the polariser comprises a right-handed 230-250° (for example 245°) twisted nematic layer with an optical thickness of 0,75-0,85 ⁇ m (for example 0,79 ⁇ m)
- the second layer, placed closer to the cholesteric colour filter layer comprises a left-handed - 240° twisted nematic layer with an optical thickness of 0,82 ⁇ m.
- the display is of the normally black type.
- the off- state of the driven LC layer is dark and the on-state is bright.
- this embodiment is described for the normally black mode, it is also possible to make a configuration in the normally white mode.
- the above two retardation films 2, 3 are inserted.
- a film 3 with the retardation of 140 nm in combination with a polariser makes circularly polarised light.
- a half -wave plate 2 of 280 nm in between a wide-band quarter-wave plate is created, resulting in a better overall dark state.
- the slow axis of the film 3, which is adjacent to the substrate makes an angle of 40° with the vertical y-axis.
- the half-wave plate 2 makes an angle of 12° with the vertical y-axis.
- the absorption axis of the polariser makes an angle of 100° with the vertical y-axis.
- twist angle and optical thickness being suitable for reflective STNs with cholesteric colour filters, besides the ones described above, are possible in order to optimise the display for different purposes. Consequently, the invention is by no means restricted to a twist angle of 240°, but other configurations differing in twist angle and optical thickness may be combined with cholesteric colour filters to give either normally black or normally white multiplexable reflective colour displays.
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Mathematical Physics (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Liquid Crystal (AREA)
- Polarising Elements (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2003519692A JP2004538515A (en) | 2001-08-03 | 2002-07-03 | Reflective liquid crystal display |
KR20047001292A KR20040030874A (en) | 2001-08-03 | 2002-07-03 | Reflective liquid-crystal display |
EP02743532A EP1423748A1 (en) | 2001-08-03 | 2002-07-03 | Reflective liquid-crystal display |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP01202951 | 2001-08-03 | ||
EP01202951.8 | 2001-08-03 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2003014820A1 true WO2003014820A1 (en) | 2003-02-20 |
Family
ID=8180749
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2002/002755 WO2003014820A1 (en) | 2001-08-03 | 2002-07-03 | Reflective liquid-crystal display |
Country Status (7)
Country | Link |
---|---|
US (2) | US6795149B2 (en) |
EP (1) | EP1423748A1 (en) |
JP (1) | JP2004538515A (en) |
KR (1) | KR20040030874A (en) |
CN (1) | CN1539094A (en) |
TW (1) | TWM250176U (en) |
WO (1) | WO2003014820A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7936426B2 (en) | 2004-07-28 | 2011-05-03 | Merck Patent Gmbh | Transflective LCD comprising a patterned retardation film |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2004029918A1 (en) * | 2002-09-25 | 2006-01-26 | シチズン時計株式会社 | Display device |
US6922221B2 (en) * | 2002-10-17 | 2005-07-26 | Research Foundation Of The University Of Central Florida | Broadband quarter-wave film device including in combination a chromatic half-wave film and a TN-LC polymeric film |
KR100792969B1 (en) * | 2003-07-23 | 2008-01-08 | 샤프 가부시키가이샤 | Liquid crystal display unit |
US7110964B2 (en) * | 2003-08-29 | 2006-09-19 | Exit41, Inc. | Order processing |
US20050049921A1 (en) * | 2003-08-29 | 2005-03-03 | Tengler Craig D. | Order processing |
US7230663B1 (en) * | 2004-08-13 | 2007-06-12 | Research Foundation Of The University Of Central Florida | Transflective LCD using multilayer dielectric film transflector |
JP2006163343A (en) * | 2004-11-15 | 2006-06-22 | Nitto Denko Corp | Elliptical polarization plate and picture display device using it |
KR20070082305A (en) * | 2006-02-16 | 2007-08-21 | 삼성전자주식회사 | Optical sheet and display apparatus having the same |
KR20080047761A (en) * | 2006-11-27 | 2008-05-30 | 삼성전자주식회사 | Liquid crystal display device |
KR101592919B1 (en) * | 2009-12-16 | 2016-02-11 | 엘지디스플레이 주식회사 | Liquid crystal display device |
KR102062828B1 (en) | 2017-09-26 | 2020-01-07 | 주식회사 엘지화학 | Optical film, optical element and display device |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5555114A (en) * | 1992-11-30 | 1996-09-10 | Sanyo Electric Co., Ltd. | Liquid crystal display with reflective color filters |
WO2000034808A1 (en) * | 1998-12-07 | 2000-06-15 | Koninklijke Philips Electronics N.V. | Patterned layer of a polymer material having a cholesteric order |
EP1072926A1 (en) * | 1999-02-15 | 2001-01-31 | Citizen Watch Co., Ltd. | Liquid-crystal display |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4435450A1 (en) * | 1993-10-04 | 1995-04-06 | Matsushita Electric Ind Co Ltd | Liquid crystal unit and projection display which uses a liquid crystal unit |
US5553114A (en) * | 1994-04-04 | 1996-09-03 | General Electric Company | Emissive coating for X-ray tube rotors |
GB2318878A (en) * | 1996-10-31 | 1998-05-06 | Sharp Kk | Reflective liquid crystal device |
EP1020755B1 (en) * | 1998-08-04 | 2005-12-07 | Kaneka Corporation | Liquid crystal display device with touch panel |
KR100417918B1 (en) * | 1999-03-12 | 2004-02-11 | 엘지.필립스 엘시디 주식회사 | Reflection type liquid crystal display device having the cell configuration with an optimum factor |
US6456346B1 (en) * | 1999-10-13 | 2002-09-24 | Citizen Watch Co., Ltd. | Color liquid crystal display device including super twisted nematic liquid crystal with molecular major axis directions parallel to a display screen horizontal axis |
JP2002148623A (en) * | 2000-08-31 | 2002-05-22 | Sharp Corp | Liquid crystal display device |
-
2002
- 2002-07-03 WO PCT/IB2002/002755 patent/WO2003014820A1/en not_active Application Discontinuation
- 2002-07-03 EP EP02743532A patent/EP1423748A1/en not_active Withdrawn
- 2002-07-03 KR KR20047001292A patent/KR20040030874A/en not_active Application Discontinuation
- 2002-07-03 JP JP2003519692A patent/JP2004538515A/en active Pending
- 2002-07-03 CN CNA02815200XA patent/CN1539094A/en active Pending
- 2002-07-30 US US10/208,348 patent/US6795149B2/en not_active Expired - Fee Related
- 2002-08-07 TW TW091212174U patent/TWM250176U/en unknown
-
2004
- 2004-08-30 US US10/929,702 patent/US20050024564A1/en not_active Abandoned
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5555114A (en) * | 1992-11-30 | 1996-09-10 | Sanyo Electric Co., Ltd. | Liquid crystal display with reflective color filters |
WO2000034808A1 (en) * | 1998-12-07 | 2000-06-15 | Koninklijke Philips Electronics N.V. | Patterned layer of a polymer material having a cholesteric order |
EP1072926A1 (en) * | 1999-02-15 | 2001-01-31 | Citizen Watch Co., Ltd. | Liquid-crystal display |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7936426B2 (en) | 2004-07-28 | 2011-05-03 | Merck Patent Gmbh | Transflective LCD comprising a patterned retardation film |
Also Published As
Publication number | Publication date |
---|---|
KR20040030874A (en) | 2004-04-09 |
TWM250176U (en) | 2004-11-11 |
US20030025861A1 (en) | 2003-02-06 |
US20050024564A1 (en) | 2005-02-03 |
US6795149B2 (en) | 2004-09-21 |
CN1539094A (en) | 2004-10-20 |
JP2004538515A (en) | 2004-12-24 |
EP1423748A1 (en) | 2004-06-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6061108A (en) | Broadband cholesteric polarizer and an optical device employing the same | |
KR100861060B1 (en) | Liquid crystal display and electronic apparatus | |
JP3291432B2 (en) | Liquid crystal display device and terminal device using the same | |
US8094265B2 (en) | Liquid crystal display | |
KR100519832B1 (en) | Crystal liquid display device and electronic equipment | |
US20030231266A1 (en) | Paper white cholesteric displays employing reflective elliptical polarizer | |
US20030231269A1 (en) | Reflective cholesteric displays without using bragg reflection | |
US6693689B1 (en) | Reflective liquid crystal display device | |
US6795149B2 (en) | Liquid crystal reflective display | |
KR100393390B1 (en) | reflective liquid crystal display device | |
JP2892913B2 (en) | Reflective liquid crystal display | |
JP2798073B2 (en) | Reflective liquid crystal display | |
JP3705184B2 (en) | Liquid crystal device and electronic device | |
JP2003228067A (en) | Liquid crystal display device and electronic apparatus | |
JP2000347187A (en) | Reflective liquid crystal display device | |
JP2003195319A (en) | Liquid crystal display device and electronic appliance | |
JP4110891B2 (en) | Liquid crystal display device and electronic device | |
JP2003330025A (en) | Liquid crystal display device and electronic equipment | |
JP2003279968A (en) | Liquid crystal display device and electronic apparatus | |
JP2004219553A (en) | Liquid crystal display device and electronic appliance | |
JP2004219552A (en) | Liquid crystal display device and electronic appliance | |
JP2003228060A (en) | Liquid crystal device and electronic apparatus | |
JP2003307726A (en) | Liquid crystal display device and electronic equipment |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): CN JP Kind code of ref document: A1 Designated state(s): CN JP KR |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH CY DE DK ES FI FR GB IE IT LU MC NL PT SE TR Kind code of ref document: A1 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2003519692 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2002743532 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1020047001292 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2002815200X Country of ref document: CN |
|
WWP | Wipo information: published in national office |
Ref document number: 2002743532 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 2002743532 Country of ref document: EP |